Health-Related Quality of Life Predictors for Adults With Physical Disabilities

Regular physical activity (PA) participation can decrease secondary health conditions related to disability and increase independent function and health-related quality of life (HRQOL; USDHHS, 2000). An integrative theoretical framework may facilitate positive PA behavior change among people with disabilities (Kosma et al., 2006). The stages of change (SOC; PA intention and behavior) of the Transtheoretical Model are stipulated to mediate the relation between the Theory of Planned Behavior (TPB) constructs and PA among adults with physical disabilities (Kosma et al., 2006). This study's first purpose was to prospectively explore the effects of past attitude (perceived consequences of PA), subjective norm (SN; perceived social pressure to be active), and perceived behavioral control (PBC; self-efficacy and controllability) on future (6-month) PA through past SOC. The second purpose examined the effect of the past TPB constructs and SOC on future HRQOL through future PA. From a previously developed database, 223 adults with physical disabilities completed online self-report standardized scales measuring attitude, SN, PBC, and the SOC. From the 208 individuals who received an email-based study invitation six months later, 147 people completed standardized self-report scales measuring PA and HRQOL. After deleting six outliers, the final sample size was 141 adults (M age = 46.04 ± 10.86 years, females = 70.9%, Caucasian = 85.1%, spinal cord injury = 22.7%, muscle/joint disorders = 18.4%). Two path analyses were conducted to analyze two models whereby PA (hrs/day) served as the mediator between the TPB constructs (attitude, SN, PBC), SOC, and the physical function (PF-Model) and the mental function (MF-Model) scores of the HRQOL scale. Both models fit the data well (RMSEA = .00). The SOC had a significant direct effect on future PA for both the PF-Model (β = .37) and the MF-Model (β = .39). The direct effect of PA on HRQOL was higher for physical function (β = .75) than for mental function (β = .31). In both models, the most important predictor of the SOC was attitude followed by PBC. The PF-Model explained more variance in PA (η² = 27%) and physical function (η² = 56%) than the MF-Model (η² = 25% for PA and 10% for mental function). Within an integrative framework (TPB/SOC), identifying the importance of PA (e.g., long-lasting effects of physical benefits) and ways to overcome PA barriers (PBC) may increase the SOC and thus PA and HRQOL. Stage-matched PA intervention programs are also warranted. Funded by NIDRR, USDE.
Keyword(s): adult physical activity/fitness, health promotion, research